a) Field of the Invention
The so called "wet" processes for developing photographs may be classified as either "continuous" or "batch" processes. In continuous processing, film or paper is moved through a series of separate tanks, each of which contains one chemical. In batch processing, film or paper is loaded into a single drum, and a sequence of chemicals are added and removed from the drum.
Generally, chemical quality is maintained by always using new chemical, or replenishing used chemical with a concentrate. The present invention concerns controlling the quality of the chemicals necessary to ensure proper processing.
The invention more particularly concerns the automatic replenishment of chemicals used to develop photographic film or paper in a batch processing machine.
b) Description of Related Art
It is known that to automatically replenish chemicals in continuous processors, concentrate is added to a processing tank based on the quantity of film or paper which has passed through the processing tank. Batch processors withdraw each chemical from the drum after its participation in developing the film or paper is completed. At present, the withdrawn chemicals are either discarded, or stored in separate containers and manually replenished for reuse.